Perfecting printing unit and tower

ABSTRACT

A continuous-blanket-contact perfecting printing tower that includes at least one perfecting printing unit that includes one-around circumference plate cylinders and a first blanket cylinder that is either one-around in circumference or two-around in circumference and also includes a second blanket cylinder that is either two-around in circumference or three-around in circumference. When the perfecting printing units are stacked in a continuous-blanket-contact tower configuration, the two-around circumference blanket cylinders and/or three-around circumference blanket cylinders allow more distance between the plate cylinders of adjacent perfecting printing units compared to continuous-blanket-contact designs that use only one-around circumference blanket cylinders. The additional distance between the plate cylinders of adjacent perfecting printing units created by the inclusion of two-around circumference blanket cylinders and/or three-around circumference blanket cylinders provides more space for more and/or larger rollers, oscillators, dampeners and/or print enhancement devices and the like, to be situated around the plate cylinders.

BACKGROUND

Perfecting printing units can be used to print one or more colors onboth sides of printing paper at the same time. A perfecting printingunit can print simultaneously on both sides of the paper by using theblanket cylinder of one side of the perfecting printing unit as theimpression cylinder for the blanket cylinder of the other side of theperfecting printing unit.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

Embodiments of the present invention relate to perfecting printing units(as shown in FIG. 1, FIG. 2, FIG. 3, and FIG. 4) and the use of theseperfecting printing units in a continuous-blanket-contact configuration(as shown in FIG. 5, FIG. 6, FIG. 7, FIG. 8, FIG. 9 and FIG. 10). Theperfecting printing unit shown in FIG. 1 and FIG. 2 includes a firstblanket cylinder that is one-around in circumference and also a secondblanket cylinder that is two-around in circumference. The perfectingprinting unit shown in FIG. 1 and FIG. 2 also includes two one-aroundcircumference plate cylinders, two inking systems and two dampeningsystems. The perfecting printing unit shown in FIG. 3 and FIG. 4includes a first blanket cylinder that is two-around in circumferenceand a second blanket cylinder that is also two-around in circumference.The perfecting printing unit shown in FIG. 3 and FIG. 4 also includestwo one-around circumference plate cylinders, two inking systems, andtwo dampening systems.

A continuous-blanket-contact configuration for a web offset pressdelivers the paper during the printing process in such a way that thepaper is not released when travelling between perfecting printing unitsstacked in a tower configuration (the orientation of the tower could beeither vertical or horizontal or otherwise). When stacked in a towerconfiguration, the second blanket cylinder of any perfecting printingunit is in contact (or nearly in contact) with the first blanketcylinder of any adjacent perfecting printing unit. The spacing betweenthe stacked perfecting printing units is close enough such that papertravelling between adjacent perfecting printing units is not releasedwhen travelling from the blanket cylinder of one perfecting printingunit to the adjacent blanket cylinder of the adjacent stacked perfectingprinting unit. Current continuous-blanket-contact printing towersconsist of perfecting printing units using only one-around circumferenceblanket cylinders. The use of two-around circumference blanket cylinders(or even three-around circumference blanket cylinders) in acontinuous-blanket-contact configuration provides many advantages overcontinuous-blanket-contact configuration designs using only one-aroundcircumference blanket cylinders.

Differently configured perfecting printing units may be stacked. Forexample, when four perfecting printing units are stacked two of theperfecting printing units may include a first blanket cylinder that isone-around in circumference and a second blanket cylinder that istwo-around in circumference. The other two of the perfecting printingunits may include blanket cylinders that are both one-around incircumference.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 and FIG. 3 illustrate exemplary plate and blanket cylinderconfigurations for perfecting printing units capable of printing onecolor on one side of the paper and simultaneously printing one color onthe other side of the paper;

FIG. 2 and FIG. 4 illustrate exemplary configurations for perfectingprinting units containing plate and blanket cylinder configurations asillustrated in FIG. 1 and FIG. 3;

FIG. 5 and FIG. 7 illustrate exemplary plate and blanket cylinderconfigurations for continuous-blanket-contact printing towers forprinting 4 colors on one side of the paper and simultaneously printing 4colors on the other side of the paper;

FIG. 6 and FIG. 8 illustrate exemplary configurations showing examplesof continuous-blanket-contact printing towers containing plate andblanket cylinder configurations as illustrated in FIG. 5 and FIG. 7; and

FIG. 9 and FIG. 10 illustrate exemplary plate and blanket cylinderconfigurations for continuous-blanket-contact printing towers forprinting 4 colors on one side of the paper and simultaneously printing 4colors on the other side of the paper.

DETAILED DESCRIPTION

Embodiments of the present invention now will be described more fullyhereinafter with reference to the accompanying drawings, which form apart hereof, and which show, by way of illustration, specific exemplaryembodiments for practicing the invention. This invention may, however,be embodied in many different forms and should not be construed aslimited to the embodiments set forth herein; rather, these embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the invention to those skilled in theart.

A perfecting printing unit can be used to print on both sides ofprinting paper at the same time. A perfecting printing unit can printsimultaneously on both sides of the paper by using the blanket cylinderof one side of the perfecting printing unit as the impression cylinderfor the blanket cylinder of the other side of the perfecting printingunit. Each perfecting printing unit typically contains two inking anddampening systems that supply ink to the desired places on thelithographic printing plates that are normally mounted on the opposingplate cylinders. The ink reservoirs and water reservoirs are separatefor each side of the perfecting printing unit.

Four perfecting printing units may be used one after the other in acontinuous-blanket-contact arrangement to provide four-color processprinting using CMYK inks, for example. Additional perfecting printingunits could be added for six-color printing, etc. Other numbers ofperfecting printing units may be used for other configurations.

A continuous-blanket-contact printing tower typically combines multipleperfecting printing units in such a way that the paper is not releasedwhen passing from one perfecting printing unit to another. Each blanketcylinder of one perfecting unit is in contact (or nearly in contact)with the adjacent blanket cylinder of its adjacent perfecting printingunits, the spacing being close enough between adjacent blanket cylindersto not effect release of the paper. The printing of various colors in acontinuous-blanket-contact design helps to reduce color registrationerrors, including color registration errors caused by wetting of thepaper or paper tension changes (and subsequent stretching) of the paperas typically happens when paper travels released from one perfectingprinting unit to another perfecting printing unit. If the paper isallowed to travel released between perfecting units (due to the blanketcylinders between adjacent perfecting printing units being spaced toofar apart—as is the case with all non-continuous-blanket-contactdesigns), then the tension on the paper and/or the wetting of the papercauses the paper (and thus the various color images) to mis-register,stretch, or distort and thus cause misplacement and/or distortion of theindividual printed images.

Plate and blanket cylinder configurations of perfecting printing unitsthat use “one-around” circumference plate cylinders, and use at leastone “two-around” circumference blanket cylinder, are illustrated in FIG.1, FIG. 2, FIG. 3, and FIG. 4. A one-around circumference plate cylinderis a plate cylinder that is capable of carrying one or more lithographicprinting plates and having a circumference that is sufficient totransmit an image equal in size to the image area of a one-aroundcircumference blanket cylinder and half the image area of a two-aroundcircumference blanket cylinder.

In FIGS. 1 and 2, the first half (110, 210) of each perfecting printingunit contains a blanket cylinder that is “one-around” in circumference.The one-around circumference blanket cylinder is typically nearly equalin circumference to the one-around circumference plate cylinder. (Platecylinders as well as blanket cylinders can have larger integercircumference ratios depending on printing requirements.) In FIGS. 1 and2, the second half (120, 220) of each perfecting printing unit containsa blanket cylinder that is “two-around” in circumference (i.e. has twicethe circumference of the blanket cylinder in the first half of theperfecting printing unit). The one-around circumference blanket cylinderand the two-around circumference blanket cylinder serve as each other'simpression cylinder and each of those two blanket cylinders act as theimage transfer cylinder for its corresponding one-around circumferenceplate cylinder (both blanket cylinders act as the image transfercylinder for a one-around circumference plate cylinder). As in aconventional perfecting printing unit, one blanket cylinder typicallyserves as the impression cylinder for the opposing blanket cylinder.

In FIGS. 3 and 4, the first half (310, 410) of each perfecting printingunit contains a blanket cylinder that is “two-around” in circumference.The two-around circumference blanket cylinder is typically nearly twicethe circumference of the one-around circumference plate cylinder. (Platecylinders as well as blanket cylinders can have larger integercircumference ratios depending on printing requirements.) In FIGS. 3 and4, the second half (320, 420) of each perfecting printing unit containsa blanket cylinder that is also “two-around” in circumference. The firsttwo-around circumference blanket cylinder and the second two-aroundcircumference blanket cylinder serve as each other's impression cylinderand each of those two blanket cylinders act as the image transfercylinder for its corresponding one-around circumference plate cylinder(both blanket cylinders act as the image transfer cylinder for aone-around circumference plate cylinder). As in a conventionalperfecting printing unit, one blanket cylinder typically serves as theimpression cylinder for the opposing blanket cylinder.

When stacked one on top of the other, the perfecting printing units forma continuous-blanket-contact design for a perfecting printing towercapable of printing using multiple colors of inks (the orientation ofthe tower could also be horizontal, in which case the perfectingprinting units would be stacked next to each other horizontally to forma continuous-blanket-contact design—and other orientations could be usedas well).

In FIG. 5 and FIG. 6, a typical blanket cylinder configuration is shownwith every second blanket cylinder (510, 520, 530, and 540) beingtwo-around in circumference rather than one-around in circumference asin the opposing side. Stacking of perfecting printing units, each havinga two-around circumference blanket cylinder along with a one-aroundcircumference blanket cylinder (as shown in FIG. 5 and FIG. 6) allowsmore space between adjacent stacked perfecting printing unit's platecylinders than current continuous-blanket-contact designs that use onlyone-around circumference blanket cylinders. The additional space betweenadjacent perfecting printing unit's plate cylinders is obtained whilemaintaining the advantage of the continuous-blanket-contactconfiguration and maintaining the advantage of a low profile for theprinting tower.

In FIG. 7 and FIG. 8, a typical blanket cylinder configuration is shownwherein every blanket cylinder (710, 715, 720, 725, 730, 735, 740 and745) is two-around in circumference rather than one-around incircumference. Stacking of perfecting printing units, each having atwo-around circumference blanket cylinder along with a second two-aroundcircumference blanket cylinder (as shown in FIG. 7 and FIG. 8) allowsmore space between adjacent perfecting printing unit's plate cylindersthan current continuous-blanket-contact designs that use only one-aroundcircumference blanket cylinders. Additional space between adjacentperfecting printing unit's plate cylinders is obtained while maintainingthe advantage of the continuous-blanket-contact configuration andmaintaining the advantage of a low profile for the printing tower.

The two-around circumference blanket cylinders (as shown in FIG. 5, FIG.6, FIG. 7, and FIG. 8), for example, allow for more and/or largerrollers, oscillators, dampeners and/or print enhancement devices and thelike, to be situated around the plate cylinders due to the increasedspace provided by using the double circumference blanket cylinders(triple circumference blanket cylinders could also be used). Theincreased space also allows for less printing challenges caused by heatbuildup. Additionally, larger gears and other components, or alternativedesigns that require more space, can be used to increase the durabilityand effectiveness of the printing unit.

Accordingly, when the perfecting printing units are stacked in a towerconfiguration, the space around the plate cylinders is increased withoutincreasing clearances between the last blanket cylinder of eachperfecting printing unit and the first blanket cylinder of the nextperfecting printing unit in the tower configuration (i.e. still allowingthe paper to not be released when passing from one perfecting printingunit to another). As discussed above, paper that is released andtravelling unsupported between perfecting printing units (rather thanbeing passed into immediate contact, or almost immediate contact, withthe adjacent perfecting printing unit's blanket cylinder—i.e. the papernot being released) can increase registration problems and allowpaper-stretch to occur.

FIG. 6 shows a continuous-blanket-contact printing tower illustrated ashaving a two-around blanket cylinder and a one-around blanket cylinderin each perfecting printing unit. FIG. 8 show acontinuous-blanket-contact printing tower illustrated as having atwo-around blanket cylinder along with a second two-around blanketcylinder in each perfecting printing unit. These examples demonstratethat the invention provides greater space between the plate cylinders ofadjacent perfecting printing units than currentcontinuous-blanket-contact designs that use only one-aroundcircumference blanket cylinders while maintaining the advantage of acontinuous-blanket-contact configuration and maintaining the advantageof a low profile for the printing tower (although the height isincreased compared to designs using only one-around circumferenceblanket cylinders due to the size difference of the two-around blanketcylinders).

Accordingly, when the perfecting printing units are stacked in a towerconfiguration, the space around the plate cylinders is increased withoutincreasing clearances between the last blanket cylinder of eachperfecting printing unit and the first blanket cylinder of the nextperfecting printing unit in the tower configuration (i.e. still allowingthe paper to not be released when passing from one perfecting printingunit to another). As discussed above, paper that is released andtravelling unsupported between perfecting printing units (rather thanbeing passed into immediate contact, or almost immediate contact, withthe adjacent perfecting printing unit's blanket cylinder—i.e. the papernot being released) can increase registration problems.

In FIG. 9 and FIG. 10, stacked perfecting printing units are shown in acontinuous-blanket-contact tower configuration. FIG. 9 illustrates afirst ordering of the stacked perfecting printing units and FIG. 10illustrates a second ordering of the stacked perfecting printing units.FIG. 9 shows a first perfecting printing unit 910 and a third perfectingprinting unit 930, both of which include a first blanket cylinder thatis one-around in circumference and a second blanket cylinder that istwo-around in circumference. Alternatively, the second blanket cylindermay be three-around in circumference in first perfecting printing unit910 and the third perfecting printing unit 930. FIG. 9 shows the secondperfecting printing unit 920 and the fourth perfecting printing unit 940each having two blanket cylinders and two plate cylinders that areone-around in circumference.

FIG. 10 shows a first perfecting printing unit 1010 and a thirdperfecting printing unit 1030 each having two blanket cylinders and twoplate cylinders that are one-around in circumference. The secondperfecting printing unit 1020 and fourth perfecting printing unit 1040each include a first blanket cylinder that is one-around incircumference and a second blanket cylinder that is two-around incircumference. Alternatively, the second blanket cylinder may bethree-around in circumference in the second perfecting printing unit1020 and the fourth perfecting printing unit 1040.

The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended.

1. A perfecting printing unit comprising: a first blanket cylinder thatis at least one-around in circumference; a second blanket cylinder thatis at least two-around in circumference, wherein the first blanketcylinder and the second blanket cylinder serve as impression cylindersfor each other; plate cylinders that are one-around in circumference;two inking systems; and two dampening systems.
 2. The perfectingprinting unit of claim 1, wherein the first blanket cylinder istwo-around in circumference and the second blanket cylinder istwo-around in circumference.
 3. The perfecting printing unit of claim 1,wherein the first blanket cylinder is one-around in circumference andthe second blanket cylinder is three-around in circumference
 4. Theperfecting printing unit of claim 1, wherein the first blanket cylinderis one-around in circumference and the second blanket cylinder istwo-around in circumference
 5. A perfecting printing tower comprisingmultiple stacked perfecting printing units, comprising: a firstperfecting printing unit, comprising: a first blanket cylinder that isat least one-around in circumference; a second blanket cylinder that isat least one-around in circumference, wherein the first blanket cylinderand the second blanket cylinder serve as impression cylinders for eachother, and wherein the first blanket cylinder contacts (or nearlycontacts) the second blanket cylinder of any adjacent perfectingprinting unit stacked prior to the perfecting printing unit; and whereinthe second blanket cylinder contacts (or nearly contacts) the firstblanket cylinder of any adjacent perfecting printing unit stackedsubsequent to the perfecting printing unit; plate cylinders that areone-around in circumference; two inking systems; and two dampeningsystems; and a second perfecting printing unit, comprising: a firstblanket cylinder that is at least one-around in circumference; a secondblanket cylinder that is at least two-around in circumference, whereinthe first blanket cylinder and the second blanket cylinder serve asimpression cylinders for each other, and wherein the first blanketcylinder contacts (or nearly contacts) the second blanket cylinder ofany adjacent perfecting printing unit stacked prior to the perfectingprinting unit; and wherein the second blanket cylinder contacts (ornearly contacts) the first blanket cylinder of any adjacent perfectingprinting unit stacked subsequent to the perfecting printing unit; platecylinders that are one-around in circumference; two inking systems; andtwo dampening systems.
 6. The perfecting printing tower of claim 5,wherein the first blanket cylinder is two-around in circumference andthe second blanket cylinder is two-around in circumference for each ofthe perfecting printing units.
 7. The perfecting printing tower of claim5, wherein the first blanket cylinder is one-around in circumference andthe second blanket cylinder is three-around in circumference for each ofthe perfecting printing units.
 8. The perfecting printing tower of claim5, wherein the first blanket cylinder is one-around in circumference andthe second blanket cylinder is two-around in circumference for each ofthe perfecting printing units.
 9. The perfecting printing tower of claim5, wherein the first blanket cylinder and the second blanket cylinder ofthe first perfecting printing unit is one-around in circumference andthe first blanket cylinder of the second perfecting printing unit isone-around in circumference and the second blanket cylinder of thesecond perfecting printing unit is either two-around in circumference orthree-around in circumference.
 10. The perfecting printing tower ofclaim 5, wherein the first blanket cylinder of the first perfectingprinting unit is one-around in circumference and the second blanketcylinder of the first perfecting printing unit is either two-around incircumference or three-around in circumference and the first blanketcylinder and the second blanket cylinder of the second perfectingprinting unit is one-around in circumference.
 11. A method for printingusing multiple stacked perfecting printing units in acontinuous-blanket-contact perfecting printing tower configuration,comprising: receiving paper to print; feeding the paper to a firstperfecting printing unit; and feeding the paper from the firstperfecting printing unit to the next perfecting printing unit and thento any further subsequent perfecting printing units in the tower whileproviding for the paper to not be released when passing from oneperfecting printing unit to another, wherein one of the perfectingprinting units includes: plate cylinders that are one-around incircumference; a first blanket cylinder that is at least one-around incircumference; a second blanket cylinder that is at least one-around incircumference; two inking systems; and two dampening systems, andwherein another of the perfecting printing unit includes: platecylinders that are one-around in circumference; a first blanket cylinderthat is at least one-around in circumference; a second blanket cylinderthat is at least two-around in circumference; two inking systems; andtwo dampening systems.
 12. The method of claim 11, wherein the firstblanket cylinder is two-around in circumference and the second blanketcylinder is two-around in circumference for each of the perfectingprinting units.
 13. The method of claim 11, wherein the first blanketcylinder is one-around in circumference and the second blanket cylinderis three-around in circumference for each of the perfecting printingunits.
 14. The method of claim 11, wherein the first blanket cylinder isone-around in circumference and the second blanket cylinder istwo-around in circumference for each of the perfecting printing units.15. The method of claim 11, wherein the first blanket cylinder and thesecond blanket cylinder of the first perfecting printing unit isone-around in circumference and the first blanket cylinder of the secondperfecting printing unit is one-around in circumference and the secondblanket cylinder of the second perfecting printing unit is eithertwo-around in circumference or three-around in circumference.
 16. Themethod of claim 11, wherein the first blanket cylinder for the firstperfecting printing unit is one-around in circumference and the secondblanket cylinder of the first perfecting printing unit is eithertwo-around in circumference or three-around in circumference and thefirst blanket cylinder of the second perfecting printing unit isone-around in circumference and the second blanket cylinder of thesecond perfecting printing unit is one-around in circumference.